Question about "Dust" in Lens

Often when I'm reading Buy & Sell sections I read disclosures that "Lens has some minor dust in it but doesn't affect image quality"...etc. That seems to be fairly common. My question is:

Can dust particles in a lens be removed and if so how is that done?

Thx.

Bogino wrote in post #18555393
Often when I'm reading Buy & Sell sections I read disclosures that "Lens has some minor dust in it but doesn't affect image quality"...etc. That seems to be fairly common. My question is:

Can dust particles in a lens be removed and if so how is that done?

Thx.

Here is a 3-part answer to your question.

1.) No. If this satisfies you, stop reading now.

2.) Its true. Dust in a lens will not affect IQ. If this satisfies you, stop reading now.

3.) Yes, the dust can be cleaned out of the lens. First you must find someone with the technical expertise, and necessary hardware to do the job. Next you will need to rent a 'clean room' at NASA, or INTEL, or someplace similar. Then you must pay to transport the technician, his gear, and your lens to the clean room. Said technician may then remove said dust from said lens. When the lens is removed from the clean room to be returned to you, it will immediately start accumulating more dust. Repeat. If this is unsatisfactory, see part 1.

Bogino wrote in post #18555393
Can dust particles in a lens be removed and if so how is that done?

Dust can be cleaned out from inside a lens. . But why bother? . As soon as you get the lens back from Canon service and use it, new dust will enter the lens.

Dust gets into the inside of lenses very easily, especially zoom lenses. . It is simply ALWAYS going to be there. . But it isn't a problem at all and there is really no reason to have it removed unless there is so much that it actually affects your photos - but that would take an unbelievable amount of dust to actually do that. . Besides, it only affects images that are strongly backlit. . So unless strongly backlit images are a big part of your shooting style, the dust - even lots of it - will never be a problem at all.

Cleaning the inside of the lens is a regular part of Canon's "Check and Clean" service. . For most Canon zoom lenses, this service costs about $300.


.

If you'd like to see just how little dust affects your photos, scotch tape a dime to the center of your lens. Shoot something. My guess is you'll see nothing of it in the resulting photo. Little, teeny dust specs inside a lens showing up in a photo? Just ain't gonna happen.

Interesting responses. I was mainly curious and trying to understand the relevancy or irrelevancy of dust in lenses. Thx.

Bassat wrote in post #18555423
If you'd like to see just how little dust affects your photos, scotch tape a dime to the center of your lens. Shoot something. My guess is you'll see nothing of it in the resulting photo. Little, teeny dust specs inside a lens showing up in a photo? Just ain't gonna happen.

Have you tried this?

Dust is a perpetual issue with lenses. Any lens that either focuses or zooms is going to accumulate a bit of it. I've had some 40+ year old lenses with a slight amount, and some much newer ones with a relatively large amount. I've never seen evidence of it in a photo.

Dust on your sensor can show up, and is more likely to be visible at very small apertures.

Archibald wrote in post #18555437
Have you tried this?

Not until just now. Sorry for the poor manual focus. If a dime and that piece of tape have this little effect on a photo, my guess remains that you will NEVER see lens dust in a photo.

Bassat wrote in post #18555465
Not until just now. Sorry for the poor manual focus. If a dime and that piece of tape have this little effect on a photo, my guess remains that you will NEVER see lens dust in a photo.

Hosted photo: posted by Bassat in
./showthread.php?p=185​55465&i=i63563412
forum: Canon Lenses

Hosted photo: posted by Bassat in
./showthread.php?p=185​55465&i=i215813135
forum: Canon Lenses

Ha ha, I never thought I could get someone to tape a dime to their lens!

Here is my result of placing a small (approx 3x5 mm) piece of paper on my lens. Foreign material most certainly will affect image quality, but its effects depend on where it is in the lens and on settings.

I agree, though, that small dust particles, especially deep inside the lens, are not likely to affect the picture.

Bogino wrote in post #18555432
Interesting responses. I was mainly curious and trying to understand the relevancy or irrelevancy of dust in lenses. Thx.

I think it is mainly for a seller of the lens to be forthcoming in their description to potential buyers that, yes there is a little bit of dust specks in the lens and no, the resulting images will not
be affected at all.
This way, a buyer can't come back and say, "Hey! You didn't say there was dust in the lens!"
To further illustrate Bassat's post about the dime, there is an interesting article where a guy sacrifices a lens to show how much obstruction a lens would endure before actually producing an image that was drastically affected. He eventually shatters the front element and still produces viewable images.
Ah, found it.
http://kurtmunger.com/​dirty_lens_articleid35​.html

Archibald wrote in post #18555477
Ha ha, I never thought I could get someone to tape a dime to their lens!

Here is my result of placing a small (approx 3x5 mm) piece of paper on my lens. Foreign material most certainly will affect image quality, but its effects depend on where it is in the lens and on settings.

I agree, though, that small dust particles, especially deep inside the lens, are not likely to affect the picture.

Hosted photo: posted by Archibald in
./showthread.php?p=185​55477&i=i60849396
forum: Canon Lenses

Agreed. Focal length, focus distance, and aperture all affect the degree of visibility. Notice I selected settings to minimize the effect. ߘ

That is the video I was looking for!

Archibald wrote in post #18555477
Ha ha, I never thought I could get someone to tape a dime to their lens!

Here is my result of placing a small (approx 3x5 mm) piece of paper on my lens. Foreign material most certainly will affect image quality, but its effects depend on where it is in the lens and on settings.

I agree, though, that small dust particles, especially deep inside the lens, are not likely to affect the picture.

It's been my experience that dust on the sensor, rear element, or "deep inside the lens", is more likely to be visible in the image, especially when small apertures are involved. (f/16, f/22, etc)

msowsun wrote in post #18555494
It's been my experience that dust on the sensor, rear element, or "deep inside the lens", is more likely to be visible in the image, especially when small apertures are involved. (f/16, f/22, etc)

Sensor - yes, of course, but we are talking about dust in a lens.

It would be hard for us to test how things inside a lens affect the image. My "deep inside the lens" comment is based on the observation that aperture blades don't show in the image, therefore foreign objects close to the aperture blades likewise would not show.

Bassat wrote in post #18555423
If you'd like to see just how little dust affects your photos, scotch tape a dime to the center of your lens. Shoot something. My guess is you'll see nothing of it in the resulting photo. Little, teeny dust specs inside a lens showing up in a photo? Just ain't gonna happen.

Might be better if you said "Shoot something at a wide open f-stop".